Histopathological changes induced by ergasilid parasitic infections on the gills of economically important fish from Batticaloa lagoon were investigated from October 2003 to November 2004. Anabas sp, Ambassis gymnocephalus, Chanos chanos, Cirrhinus mrigala, Etroplus suratensis, E. maculatus, Hemirhamphus sp, Leiognathus splendens, Lutjanus sp, Mugil cephalus, Nematalosa nasus, Oreochromis mossambicus, Siganus lineatus, S. oramin, Tachysurus sp, Terapon jarbua and Triacanthus brevirostris were naturally infected with the ergasilids viz. Ergasilus sieboldi, E. parvitergum, and Dermoergasilus sp. Intensity of infection ranged from 0 to 30 ergasilids per host fish. Histopathological investigations of infected gills showed extensive tissue damage due to attachment and feeding of ergaslids. Ergasilus sp attached close to the base of the filaments near the gill arch and the pressure exerted by the parasite attached to the lateral margin of the gill filaments induced atrophy of the secondary lamellae. Tissue reactions included hyperplasia and mucous cell proliferation of the gill epithelium and damaged primary and secondary lamellae. In addition, considerably high numbers of eosinophilic granular cells and rodlet cells were noticed in the gills of the infected fish. Histopathological changes induced by the ergasilid infections would adversely affect the proper functioning of the gills of these host fish. Mass mortalities of the fish inhabiting Batticaloa lagoon which occurred during April and May 2004 may be attributed to the infection of the fish gills by these ergasilids.

Sustainable Marine Fisheries Development K. SIVASUBRAMANIAM Abstract Sustainable development in the fisheries sector has been attempted over a considerable period of time but a high degree of success has...

Leaf Litter Decomposition in the Mangrove Ecosystems of Dutch Bay M.D. AMARASINGHE Abstract The ecological significance of mangals stems from their high primary productivity and the capacity to support...

Environmental Implications of Chromium in Tannery Wastes in the Kelani Estuarine Water P.K.M. WJEGOONAWARDANE, S.Y. NAMARATHNE, and W.D. RATNASOORIYA Abstract The Kelani estuarine water which receives effluent of two...

Indicator Organisms of Environmental Conditions in a Lotic Water body in Sri Lanka G.A.R.K. GAMLATH and M.J.S. WIJEYARATNE Abstract The species diversity and abundance of benthic invertebrates and some...

Pricing Mangrove Resources and Amenities M. SIVAKLMAR, W. ROBERT FERNANDO and P. STEELE Abstract Natural habitats such as mangroves could be conserved and sustainably managed only if local communities...

Toxicity of Chlorpyrifos and Ditmethoate to Fingerlings of the Nile Tilapia, Oreochromis niloticits-: Cholinesterase Inhibition A PATHIRATNE and P ATHAUDA Abstract Toxicity of chlorpyrifos and dimethoate, two organophosphorus insecticides...

Water Chemistry of the Nilambe Oya, a Tributary in the Central Mahaweli Valley of Sri Lanka 1. Some Physicochemical Characteristics E.I.L. SILVA Abstract Monthly and spatial variations of temperature,...

Aquaculture Research Needs, Priorities and Capacities in Sri Lanka J.M.P.K. JAYASINGHE and A.M. JAYASEKARA Abstract Aquaculture is one of the most rapidly expanding activities which has become a major...

Efficacy of Quinaldine Sulphate as an Anaesthetic for the Ornamental Carp (Cyprinus carpio) in Simulated Packaging for Long Distance Transport M HETTIARACHCHI and S.P.S.D. SENADHEERA Abstract High cost incurred...

Tilapias and Indigenous Fish Biodiversity in Sri Lanka C. H. FERNANDO, R.R.A.R. SHIRANTHA, M.J.S. WL1EYARATNE and P.R.T. CUMARANATUNGA Abstract Some species of tilapias are now found worldwide in natural...

Bioaccumulation Potential of Three Toxic Heavy Metals in Shrimp, Penaeus monodon from Different Fractions of the Culture Environment S.P.S.D. SENADHEERA AND K.A.S. PATHIRATNE Abstract Concentrations of three toxic heavy...

Perspectives and Economic Potential of Aquaculture of Tilapia: Experience in North-eastern Brazil Useful to Other Regions of the World M.A. IGARASHl, M.A. DE OLIVEIRA AND J.J.S GURGEL Abstract Brazil...

Instruments for global fisheries management - A review A. HETTIARACHCHI Abstract The impact of uncontrolled expansion of fishing activities on living marine resources has been a subject of discussion...

Population dynamics of three commercially important bivalve species (Family: Veneridae) in Puttalam lagoon and Dutch bay, Sri Lanka H.M.P. KITHSIRI, M.J.S. WIJEYARATNE AND U.S. AMARASINGRE Abstract The present study...

Population dynamics of Indian mackerel Rastrelliger kanagurta in northwestern coastal waters of Sri Lanka P.A.T. FERNANDO Abstract The population dynamics of Rastrelliger kanagurta from the northwestern coastal waters of...

Limnology of Kandy Lake before the outbreak of cyanobacteria bloom in May 1999. I. Physicochemical characteristics E.I.L. SILVA AND S.R.M.S. SAMARADIWAKARA Abstract The Kandy Lake, a man-made water body,...

Limnology of Kandy Lake before the outbreak of cyanaobacteria bloom in May 1999. II Photosynthetic primary production E.I.L. SILVA AND S.R.M.S. SAMARADIWAKARA Abstract In situ photosynthetic rates and chlorophyll-a...

Limnology of Kandy Lake before the outbreak of a cyanobacteria bloom in May 1999. III. Phytoplankton composition and succession E.I.L. SILVA AND S.R.M.S. SAMARADIWAKARA Abstract Composition and succession of...

Community structure of zooplankton and trophic status of some inland reservoirs in the low country intermediate zone of Sri Lanka S.M.A.I. Sangakkara, M.J.S. Wijeyaratne Abstract Diversity and abundance of...

Two species of angelfish (Pomacanthidae) new to Sri Lanka ARJAN RAJASURIYA AND NISHAN PERERA Abstract Two species of angelfish, namely Apolemichthys trimaculatus and Centropyge flavicauda, that have not been...

Population dynamics of Gerres abbreviatus Bleeker, 1850 from the Parangipettai waters, Southeast coast of India. S. KUGANATHAN Abstract The population dynamics of Gerres abbreviatus from the Parangipettai waters, Southeast...

Selective control of marine algal species by electrolysis treatment. SAMAN WIJESEKARA. R.G, NAKAO NOMURA AND MASATOSHI MATSUMURA Abstract This paper deals with the application of electrolysis technology for the...

Diversity of macrobenthic community in the Negombo estuary, Sri Lanka with special reference to environmental conditions. D.D.G.L. DAHANAYAKA* AND M.J.S. WIJEYARATNE Abstract Benthic animals are generally considered to be...

Sri Lanka Association for Fisheries and Aquatic Resources (SLAFAR) is a non-profit oriented voluntary organization formed by scientists, academics, technologists, developers, and entrepreneurs to address issues related to the utilization, management, and governance of fisheries and aquatic resources and associated ecosystems in Sri Lanka.